AU2015238902B2

AU2015238902B2 - Ceiling-embedded air conditioner

Info

Publication number: AU2015238902B2
Application number: AU2015238902A
Authority: AU
Inventors: Takehiko NAKAMOTO
Original assignee: Fujitsu General Ltd
Current assignee: Fujitsu General Ltd
Priority date: 2014-10-10
Filing date: 2015-10-09
Publication date: 2020-10-22
Anticipated expiration: 2035-10-09
Also published as: PL3006839T3; EP3006839A1; CN105509144B; JP2016080209A; EP3006839B1; US11162691B2; ES2794614T3; AU2015238902A1; US20160102872A1; JP6458984B2; CN105509144A

Abstract

A ceiling-embedded air conditioner includes: a ceiling-embedded casing body; a turbo fan that is disposed inside the casing body; a heat exchanger that is disposed inside the casing body on an outer peripheral side of the turbo fan; and an electrical equipment box that is disposed along a part of the heat exchanger at the upstream side of a ventilation direction. The casing body has a square shape with first to fourth side plates. The heat exchanger has first to fourth heat exchange portions bent along the first to fourth side plates respectively. An end portion of the first heat exchange portion and an end portion of the fourth heat exchange portion are disposed at a corner for tube connection out of the four corners of the casing body. The electrical equipment box is disposed to extend from the corner for tube connection toward the first heat exchange portion and the fourth heat exchange portion. 17 1/4 FIG. 1 2 22b 22d2a 32,2,321 4232 32,321 3 4 3 1 FIG. 2 22b • 22c 22d 22a 23 71 20 24 92a 9 a 5 9 19 9b 92b72 7 531A

Description

1/4

FIG. 1 2

22b

22d2a

32,2,321

4232 32,321 4 33

1

FIG. 2 22b • 22c

22d 22a

24 23 71 20 92a 9 a 5 9 19 92b72 9b 7

531A

CEILING-EMBEDDED AIR CONDITIONER CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Japanese Patent Application No.

2014-209379 filed with the Japan Patent Office on October 10, 2014, the entire content

of which is hereby incorporated by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a ceiling-embedded air conditioner. More

specifically, the present disclosure relates to an attachment structure of an electrical

equipment box.

2. Description of the Related Art

The ceiling-embedded air conditioner has a casing body including a heat

exchanger and a blower (turbo fan). The casing body is embedded in a space formed

between a ceiling slab and a ceiling panel. A flat square decorative panel is attached to

the lower surface of the casing body. The decorative panel has an air inlet and an air

outlet.

An air inlet is disposed at the center of a decorative panel. Rectangular air

outlets are disposed to surround the four sides of the air inlet. A suction grill with a

dedusting filter is provided at the air inlet of the decorative panel.

In the configuration described in JP-A-2010-78266, the casing body is a cuboid

in shape. The turbo fan is disposed at the center of the casing body. The heat

exchanger is disposed to surround the outer periphery of the turbo fan. A bell-mouth is provided between the air inlet and the turbo fan. The bell-mouth guides the air, which is taken into the casing body from the air inlet, to the inside of the turbo fan.

The bell-mouth has a base portion and a suction guide portion. The base

portion is formed in a square shape corresponding to the shape of the air inlet. The

suction guide portion is formed in a trumpet shape from the center of the base portion

toward the inside of the turbo fan. An electrical equipment box for storing electrical

equipment is disposed at a part of the base portion (refer to JP-A-2010-78266, Fig. 2).

The known electrical equipment box is formed in an elongated cuboid shape.

In addition, the known electrical equipment box is disposed along one side surface of a

casing body such that the known electrical equipment box is partially exposed to the

suction guide portion. Accordingly, the ventilation resistance becomes significantly

larger near the side of the base portion with the electrical equipment box than the

ventilation resistances in the vicinities of the three sides of the base portion without the

electrical equipment box. This deteriorates a balance of the air passing through the

heat exchanger.

According to another method disclosed in JP-A-2013-164219, an electrical

equipment box is laid out at a corner of a bell-mouth (a bent portion of a heat

exchanger) insusceptible to reduction in heat-exchange efficiency due to increased

ventilation resistance. However, the heat exchanger is also disposed at the corner and

the amount of an overlap between the heat exchanger and the electrical equipment box

remains unchanged. This also results in an imbalance of the air passing through the

heat exchanger.

SUMMARY

A ceiling-embedded air conditioner includes: a ceiling-embedded casing body that has an air suction path at the center of a lower surface and has an air blowoff path around the air suction path; a turbo fan that is disposed inside the casing body; a heat exchanger that is disposed inside the casing body on an outer peripheral side of the turbo fan; and an electrical equipment box that is disposed along a part of the heat exchanger at the upstream side of a ventilation direction. The casing body has a square shape with first to fourth side plates. The heat exchanger has first to fourth heat exchange portions bent along the first to fourth side plates respectively. An end portion of the first heat exchange portion and an end portion of the fourth heat exchange portion are disposed at a corner for tube connection out of the four corners of the casing body. The electrical equipment box is disposed to extend from the corner for tube connection toward the first heat exchange portion and the fourth heat exchange portion.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of a casing body in a ceiling-embedded air

conditioner according to an embodiment of the present disclosure as seen from the

lower side;

Fig. 2 is a perspective view of the state where a decorative panel is detached

from the casing body illustrated in Fig. 1;

Fig. 3 is a cross-sectional view of an inner structure of the casing body;

Fig. 4 is a bottom view describing the positional relation between a heat

exchanger and an electrical equipment box;

Fig. 5 is a perspective view of the electrical equipment box; and

Fig. 6 is a cross-sectional view of the electrical equipment box illustrated in Fig.

5 taken along line A-A.

DESCRIPTION OF THE EMBODIMENTS

In the following detailed description, for purpose of explanation, numerous

specific details are set forth in order to provide a thorough understanding of the

disclosed embodiments. It will be apparent, however, that one or more embodiments

may be practiced without these specific details. In other instances, well-known

structures and devices are schematically shown in order to simplify the drawing.

An object of the present disclosure is to provide a ceiling-embedded air

conditioner as described below. That is, the ceiling-embedded air conditioner allows

optimization of the structure and attachment position of an electrical equipment box.

This attains a favorable balance of the air passing through the heat exchanger to

suppress reduction in the efficiency of heat exchange.

A ceiling-embedded air conditioner (the air conditioner) according to an

embodiment of the present disclosure includes: a ceiling-embedded casing body that has

an air suction path at the center of a lower surface and has an air blowoff path around

the air suction path; a turbo fan that is disposed inside the casing body; a heat exchanger

that is disposed inside the casing body on an outer peripheral side of the turbo fan; and

an electrical equipment box that is disposed along a part of the heat exchanger at the

upstream side of a ventilation direction. The casing body has a square shape with first

to fourth side plates. The heat exchanger has first to fourth heat exchange portions

bent along the first to fourth side plates respectively. An end portion of the first heat

exchange portion and an end portion of the fourth heat exchange portion are disposed at

a corner for tube connection out of the four corners of the casing body. The electrical

equipment box is disposed to extend from the corner for tube connection toward the

first heat exchange portion and the fourth heat exchange portion.

As a preferable embodiment, the electrical equipment box is provided with first and second storage portions coupled to be orthogonal to each other and is formed in an

L shape. The first storage portion is disposed from the corner for tube connection

along the first heat exchange portion. The second storage portion is disposed from the

corner for tube connection along the fourth heat exchange portion.

In addition, when a length of the first heat exchange portion is designated as L,

a length of the fourth heat exchange portion as L2, a length of the first storage portion

as L3, and a length of the second storage portion as L4, the electrical equipment box is

preferably formed to satisfy the following conditions:

L3 1/2 x Li; and

L4 1/2 x L2.

Furthermore, the electrical equipment box preferably has a tapered surface at a

corner between a top surface and a side surface exposed to a ventilation side.

According to the air conditioner, the electrical equipment box is disposed in an

L shape along the heat exchange portions of the heat exchanger from the corner of the

casing body as a starting point where the end portions of the heat exchanger are

disposed at predetermined spacing therebetween. Accordingly, the portion of the

electrical equipment box overlapping the heat exchanger can be split into right and left

sides. This improves the balance of the air passing through the heat exchanger. As a

result, it is possible to suppress reduction in the efficiency of heat exchange.

In addition, the electrical equipment box has the first and second storage

portions orthogonal to each other. The electrical equipment box is formed in an L

shape such that the first storage portion is disposed from the corner along the first heat

exchange portion, and the second storage portion is disposed from the corner along the

fourth heat exchange portion. This produces a favorable balance of the air passing

through the heat exchanger. Accordingly, it is possible to minimize the influence on the heat exchange portions.

Further, when the length of the first heat exchange portion is designated as L,

the length of the fourth heat exchange portion as L2, the electrical equipment box is

formed, the length of the first storage portion as L3, and the length of the second storage

portion as L4, the electrical equipment box is formed to satisfy the following

conditions:

L3 1/2 x Li; and

L4 1/2 x L2.

This makes it possible to minimize the influence on the heat exchange portions while

ensuring the required size of the electrical equipment box.

Furthermore, the tapered surface is provided at the corner of the electrical

equipment box between the top surface and the side surface exposed to the ventilation

side. Accordingly, the ventilation resistance of the air passing through the electrical

equipment box is allowed to be suppressed. This prevents reduction in the efficiency

of heat exchange.

Next, an embodiment of the present disclosure will be described with reference

to the accompanying drawings. However, the present disclosure is not limited to this.

As illustrated in Figs. 1 to 4, a ceiling-embedded air conditioner 1 includes a

cuboid-shaped casing body 2. The cuboid-shaped casing body 2 is stored in the space

formed between a ceiling slab and a ceiling panel. The casing body 2 is a box-shaped

container having a top plate 21, four side plates 22a to 22d (hereinafter, referred to as

first to fourth side plates 22a to 22d), and a bottom surface 20. The top plate 21 has a

regular square shape with chamfered corners. The first to fourth side plates 22a to 22d

are extended downward from the respective sides of the top plate 21. The bottom

surface 20 (lower surface in Fig. 1) is opened. In this embodiment, the corners of the casing body 2 are chamfered according to the shape of the top plate 21.

The bottom surface 20 of the casing body 2 is opened to the inside of the room.

An air suction path 23 that is square in cross section is formed at the center of the

bottom surface 20. An air blowoff path 24 is formed on the bottom surface 20 of the

casing body 2 to surround the four sides of the air suction path 23.

A decorative panel 3 is screwed to the bottom surface 20 of the casing body 2.

The decorative panel 3 is made of a synthetic resin and has a flat regular square shape.

A square air inlet 31 is provided at the center of the decorative panel 3. The air inlet

31 communicates with the air suction path 23 of the casing body 2. Rectangular air

outlets 32 are disposed around the air inlet 31 at four places along the respective sides

of the air inlet 31. The air outlets 32 communicate with the air blowoff path 24 at the

back surface side (ceiling surface side).

A suction grill 4 is provided to cover the air inlet 31. The suction grill 4 is a

synthetic resin molded component. The suction grill 4 is formed in a flat regular

square shape to cover the bottom surface 20 of the casing body 2.

In this embodiment, the air outlets 32 are respectively covered with electrically

opening and closing wind direction plates 321. During air-conditioning operation, the

wind direction plates 321 are opened by a rotation member not illustrated provided on

the back surface side of the decorative panel 3 to make the air outlets 32 appear.

The casing body 2 stores a turbo fan 5 as a blowing fan and a heat exchanger 6

therein. A bell-mouth 7 is disposed in the air suction path 23 ranging from the air inlet

31 to the turbo fan 5. The bell-mouth 7 guides the air taken in from the air inlet 31 to

the turbo fan 5.

As illustrated in Figs. 2 and 3, the turbo fan 5 includes a main plate 52, a

shroud 53, and a plurality of blades 54. Themainplate52hasahub521. Arotation shaft 511 of adrive motor 51 is fixed to the center of thehub 521. Theshroud53is disposed to be opposed to the main plate 52 along the direction of axis of the rotation shaft 511. The plurality of blades 54 is disposed between the main plate 52 and the shroud 53. An opening 531 is provided at the center of the shroud 53 for inserting a part of the bell-mouth 7 into the turbo fan 5.

The turbo fan 5 is disposed at almost the center of inside of the casing body 2.

The turbo fan 5 is hung and held by the drive motor (fan motor) 51 mounted on the top

plate 21. Accordingly, as the turbo fan 5 is driven to rotate, the bell-mouth 7 is under

negative pressure at the air inlet 31 side (lower side in Fig. 3). Therefore, the air taken

in from the air inlet 31 is sucked into the turbo fan 5 through the bell-mouth 7, and is

blown toward the outer peripheral direction through the blades 54.

As illustrated in Figs. 3 and 4, the heat exchanger 6 is vertically extended from

the top plate 21 to the opening in a bottom surface 20. The heat exchanger 6 is formed

in a square frame shape to surround the turbo fan 5. The heat exchanger 6 has a first

heat exchange portion 6a, a second heat exchange portion 6b, a third heat exchange

portion 6c, and a fourth heat exchange portion 6d. The first heat exchange portion 6a

is disposed in parallel to the first side plate 22a. The second heat exchange portion 6b

is disposed in parallel to the second side plate 22b. The third heat exchange portion 6c

is disposed in parallel to the third side plate 22c. The fourth heat exchange portion 6d

is disposed in parallel to the fourth side plate 22d.

In this embodiment, the heat exchanger 6 includes an elongated square

plate-like body with four bent portions. The heat exchanger 6 has a heat-radiation fin

group 61 including a large number of strip-shaped heat-radiation fins. The large

number of heat-radiation fins is disposed at predetermined spacing therebetween. In

the heat exchanger 6, a large number of heat-transfer tubes 62 are inserted into the heat-radiation fin group 61 in parallel to one another.

As illustrated in Fig. 4, the heat exchanger 6 has four bent portions 6e to 6h.

Of these bent portions, the first bent portion 6e is formed between the first heat

exchange portion 6a and the second heat exchange portion 6b. The second bent

portion 6f is formed between the second heat exchange portion 6b and the third heat

exchange portion 6c. Each of the first bent portion 6e and the second bent portion 6f is

bent at right angle.

The third bent portion 6g and the fourth bent portion 6h are positioned between

the third heat exchange portion 6c and the fourth heat exchange portion 6d. In order to

provide an installation space for a drain pump (not illustrated), the third bent portion 6g

and the fourth bent portion 6h are bent such that, when the third bent portion 6g and the

fourth bent portion 6h are combined with each other, a right angle or an approximately

right angle is formed. The fourth bent portion 6h may not be provided between the

third heat exchange portion 6c and the fourth heat exchange portion 6d. In this case,

the third bent portion 6g, which is disposed between the third heat exchange portion 6c

and the fourth heat exchange portion 6d, may be bent at right angle. Accordingly, the

first to fourth heat exchange portions 6a to 6d are bent along the first to fourth side

plates 22a to 22d of the casing body 2 respectively.

The end portions of the heat-transfer tubes 62 are drawn from an end portion

63 of the first heat exchange portion 6a and an end portion 64 of the fourth heat

exchange portion 6d in the heat exchanger 6. A U-shaped tube (not illustrated) is

coupled to the one end portion 63. At the other end portion 64, gas-side tubes are

united into one collective tube and coupled to a gas-side pipe G, and liquid-side tubes

are united into one collective tube and coupled to a liquid-side pipe L.

In this embodiment, the heat exchanger 6 is formed in a square shape in a plane view of Fig. 4 by bending one heat exchanger. Instead of this, the heat exchanger 6 may be formed by coupling four small-sized heat exchangers at the end portions.

As described above, the heat exchanger 6 is bent at the first to fourth bent

portions 6e to 6h. Accordingly, the heat exchanger 6 is bent in a square shape. In

addition, the heat exchanger 6 has the end portions 63 and 64 disposed at a

predetermined spacing therebetween.

In this embodiment, as illustrated in Fig. 4, the end portions 63 and 64 are

disposed at an upper right corner A for tube connection of the casing body 2. The

gas-side pipe G and the liquid-side pipe L are drawn outward from the corner A of the

casing body 2.

The heat exchanger 6 is connected to a reversible refrigeration cycle circuit not

illustrated that allows cooling operation and heating operation. The heat exchanger 6

serves as an evaporator to cool the air during cooling operation. Meanwhile, the heat

exchanger 6 serves as a condenser to heat the air during heating operation.

Drain pans 8 are provided at the lower end side of the heat exchanger 6 to

receive dew condensation water generated by the heat exchanger 6. The drain pans 8

are provided with gutters 81. The gutters 81 store the lower end side of the heat

exchanger 6. The dew condensation water dropped from the heat exchanger 6 is

received at the gutters 81 and drawn up by a drain pump not illustrated.

The bell-mouth 7 is composed of a synthetic resin molded component. The

bell-mouth 7 includes a base portion 71 and a suction guide portion 72 as illustrated in

Figs. 2 and 3. The bell-mouth 7 is screwed into the drain pans 8. The base portion

71 is disposed at the air inlet 31 side, and is formed in a square shape corresponding to

the shape of the air inlet 31. The suction guide portion 72 is formed in a trumpet shape

from the center of the base portion 71 toward the inside of the turbo fan 5.

The base portion 71 is a concave formed in a square shape corresponding to the

shape of the air inlet 31. A storage concave portion 73, in which the electrical

equipment box 9 described later is to be disposed, is formed in a part of the base portion

71. The storage concave portion 73 has a corner positioned above the corner A of the

casing body 2 (refer to Fig. 2). The storage concave portion 73 is extended from the

corner as a center in parallel to the first heat exchange portion 6a and the fourth heat

exchange portion 6d. The electrical equipment box 9 is stored in the storage concave

portion 73.

As illustrated in Fig. 4, the electrical equipment box 9 is disposed along a part

of the heat exchanger 6 at the upstream side of the ventilation direction. As illustrated

in Figs. 5 and 6, the electrical equipment box 9 includes a box body 91 and a lid portion

92. The box body 91 has an opened upper surface and stores a substrate and/or

electrical equipment (both not illustrated). The lid portion 92 closes the opened

surface of the box body 91. In this embodiment, the electrical equipment box 9 is

formed by bending a metal plate, for example.

The box body 91 has a first storage portion 91a and a second storage portion

91b. The box body 91 is formed in an L shape such that the first storage portion 91a

and the second storage portion 91b are orthogonal to each other. A

temperature-humidity sensor 93 is erected on the side wall of the first storage portion

91a opposed to the suction guide portion 72.

The lid portion 92 is formed in an L shape adapted to the opening of the box

body91. The lid portion 92 includes a first lid portion 92a covering the first storage

portion 91a and a second lid portion 92b covering the second storage portion 91b. The

lid portion 92 has a horizontal top surface 921 coinciding with the open surface of the

boxbody91. A tapered surface 94 is formed at the corner between the top surface 921 of the lid portion 92 and the side surface (a side surface exposed to the ventilation side)

911 of the box body 91 exposed to the suction guide portion 72.

The tapered surface 94 is an inclined surface that, when the electrical

equipment box 9 is disposed at the storage concave portion 73 (refer to Fig. 3) of the

bell-mouth 7, is formed at the corner between the top surface 921 of the lid portion 92

and the side surface 911 of the box body 91 exposed to the suction guide portion 72.

The height of the tapered surface 94 (height in the up-down direction in Fig. 6) is

gradually smaller from the upstream side to the downstream side of the ventilation

direction. Accordingly, the air flowing along the surface of the electrical equipment

box 9 can be smoothly guided toward the bell-mouth 7 through the tapered surface 94.

As illustrated in Fig. 4, the length of the first heat exchange portion 6a is

designated as Li, the length of the fourth heat exchange portion 6d as L2, the length of

first storage portion 91a as L3, and the length of the second storage portion 91b as L4.

In this case, the electrical equipment box 9 is formed to satisfy the following conditions:

L3 1/2 x Li; and

L4 1/2 x L2.

Accordingly, the amount of an overlap between the first heat exchange portion

6a and the first storage portion 91a and the amount of an overlap between the fourth

heat exchange portion 6d and the second storage portion 91b become 50% or less

respectively. This produces a favorable balance of the air passing through the heat

exchanger while ensuring the required size of the electrical equipment box. As a result,

it is possible to enhance the efficiency of heat exchange.

When the electrical equipment box 9 is disposed along the storage concave

portion 73 of the bell-mouth 7, the first storage portion 91a is disposed from the corner

A along an opposed surface 65a of the first heat exchange portion 6a (in parallel to the opposed surface 65a). Further, the second storage portion 91b is disposed from the corner A along an opposed surface 65d of the fourth heat exchange portion 6d (in parallel to the opposed surface 65d).

Accordingly, the electrical equipment box 9 is disposed from the corner A

toward the first heat exchange portion 6a and the fourth heat exchange portion 6d.

That is, the center of the electrical equipment box 9 is disposed at the corner A hardly

contributing to heat exchange. In other words, the electrical equipment box 9 is

disposed in an L shape from corner A as a starting point along the opposed surface 65a

of the first heat exchange portion 6a and the opposed surface 65d of the fourth heat

exchange portion 6d. This produces a favorable balance of the air passing through the

heat exchanger.

According to this embodiment, the electrical equipment box 9 has the first

storage portion 91a and the second storage portion 91b that are equal in length (L3: L4

= 1: 1). The lengths (and the length ratio) of the first storage portion 91a and the

second storage portion 91b may be arbitrarily changed according to the specifications as

far as the foregoing conditions (L3 1/2 x Li and L4 < 1/2 x L2) are satisfied.

As described above, according to the present disclosure, the electrical

equipment box is disposed in an L shape along the heat exchange portions of the heat

exchanger from the corner of the casing body as a starting point where the end portions

of the heat exchanger are disposed at predetermined spacing therebetween.

Accordingly, the portion of the electrical equipment box overlapping the heat exchanger

can be split into right and left sides. This improves the balance of the air passing

through the heat exchanger. As a result, it is possible to suppress reduction in the

efficiency of heat exchange.

The expressions herein indicating shapes or states such as regular square, rectangular, square, circular, vertical, parallel, right angle, the same, orthogonal, and horizontal, signify not only strict shapes or states but also approximate shapes or states shifted from the strict shapes or states, without deviating from the scope in which the operations and effects of these shapes or states can be achieved.

The foregoing detailed description has been presented for the purposes of

illustration and description. Many modifications and variations are possible in light of

the above teaching. It is not intended to be exhaustive or to limit the subject matter

described herein to the precise form disclosed. Although the subject matter has been

described in language specific to structural features and/or methodological acts, it is to

be understood that the subject matter defined in the appended claims is not necessarily

limited to the specific features or acts described above. Rather, the specific features

and acts described above are disclosed as example forms of implementing the claims

appended hereto.

Claims

1. A ceiling-embedded air conditioner comprising:

a ceiling-embedded casing body that has first to fourth side plates forming a

square shape, a lower surface arranged below the first to fourth side plates, an air

suction path at a center of the lower surface, and an air blowoff path around the air

suction path, one corner of four comers of the casing body having a gas-side pipe and

liquid side tubes and being arranged for tube connection;

a bell-mouth disposed in the lower surface of the casing body and including a

concaved base portion having a square shape with a flat bottom and a suction guide

portion in a center of the concaved base portion, the concaved base portion with the flat

bottom having an L-shape storage concave portion formed in the square shape with a

corner positioned above a corner of the casing body;

a turbo fan that is disposed inside the casing body;

a heat exchanger that is disposed inside the casing body on an outer peripheral

side of the turbo fan and has heat-transfer tubes therein, first to fourth heat exchange

portions bent along the first to fourth side plates respectively, an. end portion of the first

heat exchange portion and an end portion of the fourth heat exchange portion, the end

portions of the first and fourth heat exchange portions being spaced from each other and

disposed at the one comer of the four corners of the casing body. the storage concave

portion extending from the one corner as a center in parallel to the first heat exchange

portion and the fourth heat exchange portion;

drain pans formed separately from the bell-mouth and disposed laterally

outside the concaved base portion of the bell-mouth at lower ends of the first to fourth

heat exchange portions; and an electrical equipment box that is disposed in the L-shape storage concave portion of the concaved base portion along a part of the heat exchanger at the upstream side of a ventilation direction, and includes: a first storage portion disposed to extend from the one corner along the first heat exchange portion and having a length less than that of the first heat exchange portion; a second storage portion disposed to extend from the one corner along the fourth heat exchange portion and having a length less than that of the fourth heat exchange portion; and a corner portion coupling the first and second storage portions to be orthogonal to each other; such that the electrical equipment box is formed in an L-shape and disposed at said one corner for connection of the gas-side pipe and the liquid side tubes where the first and the fourth heat exchange portions are not present; wherein an outer line of the first storage portion along the first heat exchange portion extends from an end of the first heat exchange portion to an inner side of the one corner for the tube connection, and an outer line of the second storage portion along the fourth heat exchange portion extends from an end of the fourth heat exchange portion to the inner side of the one comer for the tube connection.

2. The ceiling-embedded air conditioner according to claim 1, wherein:

when a length of the first heat exchange portion is designated as LI, a length of

the fourth heat exchange portion as L2, a length of the first storage portion as L3, and a

length of the second storage portion as L4, the electrical equipment box is formed to

satisfy the following conditions:

L3 : 1/2 x LI; and

L4 ! 1/2 x L2.

3. The ceiling-embedded air conditioner according to either claim 1 or 2, wherein

the electrical equipment box has a tapered surface at a corner between a top

surface and a side surface exposed to a ventilation side.

4. The ceiling-embedded air conditioner according to any one of claims 1 to 3,

wherein:

the corner portion is disposed at the one corner of the casing body;

the first storage portion extends from the corner portion toward the second heat

exchange portion in parallel to the first heat exchange portion; and

the second storage portion extends from the corner portion toward the third

heat exchange portion in parallel to the fourth heat exchange portion.

5. The ceiling-embedded air conditioner according to claim 4, wherein:

the corner portion has an outer peripheral portion arranged between the end

portions of the first and fourth heat exchange portions and inclined in respect to the first

and fourth heat exchange portions; and

an inner peripheral portion arranged between the turbo fan and the outer

peripheral portion and inclined in respect to the first and fourth heat exchange portions.

6. The ceiling-embedded air conditioner according to any one of claims 1 to 5,

wherein the first storage portion has the length same as that of the second storage

portion.

7. The ceiling-embedded air conditioner according to any one of claims 1 to 6,

wherein the electrical equipment box further includes:

a first surface;

a second surface perpendicular to the first surface and at a downstream of the

first surface in the ventilation direction; and

a tapered surface inclined from the first surface to the second surface for

guiding air into the casing body so that a height of the electrical equipment box at the

tapered surface in a vertical direction of the casing body gradually reduces from the

upstream side to a downstream side of the ventilation direction.

8. The ceiling-embedded air conditioner according to any one of claims 1 to 7,

wherein the suction guide portion disposed at a center of the concaved base portion

extends toward the turbo fan, the suction guide portion having a trumpet shape with an

inner opening and guiding the air to the turbo fan, and the electrical equipment box

being arranged outside the inner opening.

9. The ceiling embedded air conditioner according to any one of claims 1 to 8,

wherein:

the comer portion of the electrical equipment box has an outer inclined portion

extending between an outer portion of the first storage portion and an outer portion of

the second storage portion;

the outer inclined portion being located between the end portions of the first

and fourth heat exchange portions.

10. The ceiling-embedded air conditioner according to claim 9, wherein:

the first to fourth heat exchange portions include a second heat exchange

portion and a third heat exchange portion;

the first and the second heat exchange portions are connected to each other;

the second and the third heat exchange portions are connected to each other;

the third and the fourth heat exchange portions are connected to each other; and

the first and the fourth heat exchange portions are not connected to each other.

11. The ceiling-embedded air conditioner according to any one of claims 1 to 10,

wherein the electrical equipment box includes a box body with an opened upper surface,

and a lid portion closing the opened upper surface.

12. The ceiling-embedded air conditioner according to claim 11, further

comprising a temperature-humidity sensor erected on a side wall of the first storage

portion that coincides with a suction side portion.